Posts filed under ‘peru’

Arsenic and other minerals have been removed from river water using solar power by a team of Peruvian and Chilean researchers.

Researchers from Peru’s National Engineering University and Chile’s Tarapacá University have photochemically purified water from the river Locumba near Tacna, a Peruvian town by the border with Chile.

The decontaminated water is used for agricultural irrigation, though depending on the level of decontamination achieved it could be used for human consumption in future.

The technology’s ease of use means it could be used in the countries involved with the research as well as Bolivia; Andean countries where natural contamination is present in many waterways.

Juan Rodríguez, coordinator of the research in Peru, told SciDev.Net that the technology is able to reduce high levels of arsenic contamination of currently 500 parts per billion (ppb) to about 30 ppb.

The researchers designed prototypes of electrochemical equipment and decontamination filters for use in rural or difficult to access areas, which for the moment can treat 20 cubic metres of water daily.

“Modular systems can process much higher volumes, so that’s what we’re trying to achieve,” Rodríguez said.

They used a photochemical system with tubes of glass or plastic to decontaminate the water. Based on reflections the tubes get solar radiation for a few hours, which can purify water contaminated with arsenic and make it suitable for consumption.

This system can also decontaminate boron and iron from water, as sunlight accelerates the rate at which minerals coagulate and can then be removed.

According to Rodríguez, this research is of importance for Bolivia, Chile and Peru because “the problem of arsenic in waterways is of natural origin and doesn’t distinguish between borders”.

This is my translation of a story written by Zoraida Portillo on the Science and Development Network, “Reducen contaminación por arsénico usando energía solar”, published on August 3, 2010.You can read the original in Spanish here.

SciDev.Net stories are published under a Creative Commons attribution license; my translation is available under the same license. Note this license is only for this page. Other works on this website are subject to other licenses; please contact me for details if you’d like to republish other parts of this site.

Exposure to antibiotics at home and in the broader environment influences the risk of children carrying antibiotic-resistant Escherichia coli bacteria, according to a study published in the The American Journal of Tropical Medicine and Hygiene.

The study was based in four areas of Peru with poor health systems, where antibiotics are used indiscriminately and without prescription. It covered coastal, mountain and jungle environments and focused on children between the ages of three months and three years.

The study suggests that environmental exposure to antibiotic-resistant E. colican be as important as the consumption of antibiotics, according to the paper’s principal author, Henry Kalter, from the School of Public Health at Johns Hopkins University.

A risk factor at home was the use of antibiotics by other family members. The study demonstrated that children who hadn’t taken particular antibiotics themselves still carried bacteria resistant to them.

At the community level, living in a place where many families raised chickens themselves was a protective factor against the transport of antibiotic-resistant bacteria. According to Kalter, high consumption of home-raised chickens probably protects a community against exposure to antibiotics. He contrasted home-raised chickens with market-bought chickens, which may be given high doses of antibiotics and therefore have high levels of antibiotic-resistantE. coli.

“An important aspect of our conclusions is that the protective effect was not due to the fact that the children were eating certain types of chicken; rather that their communities were,” he said.

Kalter suggested that communities consuming more chickens raised at home presumably had less resistant bacteria in the environment, such as in open sewers and uncovered wells.

“This study reinforces the message that exposure to antibiotics leads to the development of antibiotic resistance, by studying the role of different types of exposure on small children carrying of antibiotic-resistant E. coli,” he continued.

According to Kalter, examining these factors provides a better understanding of how antibiotic resistance spreads in the developing world.

“These findings suggest that unnecessary use of antibiotics in humans and animals should be minimised as much as possible,” he added.

“Many tons of the antibiotics consumed each year on the planet are given to stock animals. This study demonstrates that this use has a very real cost to human health,” Edward T. Ryan, president of the American Society of Tropical Medicine and Hygiene, said in a press release from Johns Hopkins University.

This is my translation of a story written by Zoraida Portillo on the Science and Development Network, “Antibióticos propician resistencia infantil a E. coli”, published on June 14, 2010.You can read the original in Spanish here.

SciDev.Net stories are published under a Creative Commons attribution license; my translation is available under the same license. Note this license is only for this page. Other works on this website are subject to other licenses; please contact me for details if you’d like to republish other parts of this site.